Acrylic Enamel: Chemically enhanced enamel formulas are the mainstay of modern refinishing products. Acrylic enamels use a catalyst to induce chemical reactions that produce a paint film of remarkable durability, chemical resistance, and gloss. Acrylic enamels can be polished like lacquer to a mirror finish.
Urethane: Similar to acrylic enamels, but using urethane resins. Urethane has most of the desirable features of acrylic enamel but with enhanced durability, although they generally dry slower.What is the difference between acrylic enamel and acrylic urethane automotive paint?
they are not water-borne.neither one is. urethane is a single stage. that means clear coat not req'd. you mix paint 4 parts(usually) to 1 part hardener, and it reacts to harden at room temp. it will still remain somewhat flexible, so you can paint the rubber or plastic bumpers without the flex additive. acrylic enamel will dry by iself, but the process is sped up with the hardener and gloss additive. it will dry hard, and will not flex with the bumpers. it needs the flex additive for that. i like the urethane to paint with. im not a professional body man or painter, but i have painted several dozen cars,and done custom work, so i can paint with the best of them. i would much rather tackle an engine or trans or electrical work, rather than paint.